ADOC, ASiC-E and PDF
PDF/A: the archival PDF for long-term storage
PDF/A helps make sure that a document will look the same in years as it did on the day it was signed.
Why an ordinary PDF is not always enough
An ordinary PDF can depend on external fonts, on links, or on how a particular reader interprets it. For archival storage what matters is that the file stands on its own.
PDF/A is a standard in the ISO 19005 family, made for the long-term preservation of electronic documents. Tvarka states publicly that it prepares PDF/A-2b as part of the document signing chain.
Where it helps in Tvarka
PDF/A is particularly useful for contracts, accounting documents, Manager resolutions, powers of attorney, and anything whose authenticity may have to be shown after a long interval.
When Tvarka converts a DOCX or another document to PDF/A in the background, what gets signed is a version that renders the same way every time.
Frequently asked questions
Does PDF/A open in an ordinary PDF reader?
Yes. PDF/A is part of the PDF family, with restrictions meant for archiving.
Does PDF/A change the content of the document?
The aim is not to change content but to prepare a self-contained version that renders predictably. The original can stay in the Tvarka version history.
Is PDF/A the same thing as ADOC?
No. PDF/A is a document format; ADOC is a container that can hold documents, metadata and signatures.
Sources
- ISO 19005-2: the PDF/A-2 standard Checked: 2026-06-12
- Tvarka PDF/A tool page Checked: 2026-06-12
- Tvarka Sign: public product page Checked: 2026-06-12